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%I #17 Jun 12 2021 22:32:25
%S 5,0,9,0,6,7,8,7,2,9,3,1,7,1,6,5,6,2,2,9,7,8,6,7,7,7,1,9,9,0,7,4,9,8,
%T 4,3,7,9,7,3,8,5,1,6,8,0,2,0,9,3,7,5,6,1,6,5,2,5,1,2,7,2,4,3,1,1,0,6,
%U 5,3,6,0,2,5,8,4,9,1,7,7,9,7,4,3,9,3,5
%N Decimal expansion of Sum_{n>=0} A000108(n)/n!.
%F Equals e^2 * BesselI(2,2) = A072334 * A229020. - _Amiram Eldar_, May 17 2021
%e 5.09067872931716562297867771990749843797385168020937561652512724311065360258491...
%t RealDigits[E^2 * BesselI[2, 2], 10, 100][[1]] (* _Amiram Eldar_, May 17 2021 *)
%o (PARI) suminf(n=0, (2*n)!/(n!*n!*(n+1)!)) \\ _Michel Marcus_, May 16 2021
%Y Cf. A000108, A072334, A229020.
%K cons,nonn
%O 1,1
%A _Ya-Ping Lu_, May 10 2021